Internal combustion engine for gaseous and liquid fuels



Nov. 24, '1931. K.SCHMIDT 1,333,265

INTERNAL COMBUSTION ENGINE FOR GASEOUS AND LIQUID FUELS Filed J une 23, 1928 5 Sheets-Sheet. l

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NOV. 24', 1931- K, sc 1,833,265,

INTERNAL COMBUSTION ENGINE FOR GASE'OUS AND LIQUID FUELS Filed June 23, 1928 5 Sheets-Sheet, 2

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INTERNAL COMBUSTION ENGINE FOR GASEQUS AND LIQUID FUELS Filed June 23, 1928 3 Sheets-Sheet, 3

Patented Nov. 24, 1931 UNITED sTA'ras PATENT oFiu'cE xunr scanner, or comennnonwnmn, GERMANY, assrenoa 'I'O uoroannrazemx nnu'rz, ax'rmncnsnuscnm, or eoLoeNnmEU-r z, GERMANY INTERNAL comwsrron' merits non easnous maroon) rams Application filed June 23, 1928, Serial No. 287,846, and in Germany, June 23, 1927.

The invention has among its objects the provision of an internal combustion engine which will secure the advantages of both a a motor operating on liquid fuel and a motor operating on gaseous fuel, while eliminating the disadvantages of both. It will be understood that a motor operating on liquid fuel, as distin ished from one operating on gaseous fue commonly may be more readily 1 placed in operation and commonly is more ada table for use in situations where it is sub ected to variable loads-or to suddenly applied and continuous overloads. However, due to the reater fuel cost, motors operating on liquid fiiel are more expensive to operate than those' operating on gaseous fuel, especially where the latter is supplied from a gas generator or is natural as.

The invention will be est understood from the following description when read in the light of the accompanying drawings of several embodiments of the invention, while the scope of the invention will be more particularly pointed out in the appended claims.

In the drawings ,Fig. 1 more or less diagrammatically shows a motor and associated apparatus arranged for operating with liquid and gaseous fuel according to the invent1on;

Fig. 2 shows a modified form of the motor and associated apparatus;

Fig. 3 is a. diagram illustrating graphically the relation between the lift of the governor sleeve and calorific values of gaseous and liquid fuel mixtures supplied to the motor;

Fig. 4 shows a modification in which provision is made for preheating the air supplied to the motor; e

Fig. 5 is an indicator diagram of the motor according to Fig. 4;

Flg. 6 shows. a modification in which provision is made for, precompressing the air supplied to the motor; and 17 1g. 7 is an indicator diagram of the motor 6 according to Fig. 6.

oil (acc. to Fig. 3 until the balance between In Fig. 1 is shown an internal combustion engine or using aseous anddiquid fuels, which en ine has t e inlet and mixing valve 6. 'To this valve the gas and air pipes a and d are connected. The lift of valve b ma be altered by the movable fulcrum armf, w ich latter is actuated by governor e. The points g are the fixed centre points of the governor gearin s. The effective movement of the action 0 the valve 6 is caused by the camshaft h. The governor also actuates by means of the gearings z, the overflow valve is of the oil pump m.

The governing is effected (see Fig. 3) in such a way, that the combustion engme first works as a gas engine entirely, and is changed from gas to oil-working under predetermined conditions, as when the gas supply fails or is 1 insufficient to meet the load.

For instance, if the supply of gas is diminished, the sleeve of the governor will lower-the load on the engine may be a continuous one-and cause the introduction of work and load is regained. In this case it is to be understood, ,that the oil-pump injects the fuel directly into the cylinder.

Analogically the governor, in its lowest position may open the throttling device of a carburetor in such away, that the cylinder is charged with a benzine-air mixture instead with a gas-air mixture. p 1

In Fig.1 the method of working of the governor is shown, The governor is in the position, which corresponds to point A of Fig. 3, in which position the a mission of gas has reached almost its highest degree." on the ther hand the lever n of the governor device ofthe fuel pump is in such a position that the overflow valve lc' just is clo at the lowest position of plunger 0. If the governor sleeve slides below the position .shown in Fig, 1 the'overflow valve will be closed during the delivery stroke. ofthe plunger for some time, and the fuel pump 00 therefore is able to discharge oil. If the engine speed then increases in such a way that the governor sleeve rises to above the position. shown in the drawings, the lever n of the fuel pump comes to such a position, that the overflow-valve is opened i-n'every position of the plunger, and therefore the pump is not working.

It is sometimes undesirable to keep 0 en the gas conduit during sole oil working. dvantageously according to this invention provision may be made for governing of the motor in such a way, that, after the charge of oil has increased to a certain value, the gas admission is throttled. This is shown in Fig. 2. To the movable fulcrum arm 7 a lever p is jointed, which latter works the throttle valve 8 through gearing g and lever r. Thespring t will draw the lever 1' towards the stop u, that means it will open the throttle valve as much as possible. Theupper sleeve of the rod q provides, that-the throttle valve will remain in open position, if the governor sleeve rises (gas working). If the governor sleeve lowers oil working) the throttle valve is closed when it reaches a certain position.

The above described governing relates as well to an internal combustion engine working with a gas-air mixture or with a liquid fuel of low ignition point as .to one working with a gas-air-mixture of high ignition point and an'oil of high boiling point. In both cases the compression for gas \and oil working may be kept the same.

If however the engine is used for gas-air mixtures of low igmtion points and oil of higher boiling point, the tem erature of compression may be different. This maybe done, according to the invention, in such way that, under the control of the governor, a heating device, for example an electric heating coil, may be brought into operation for heating the suction air.

0 One exam le of this arrangement is shown in Flg. 4. n the air suction tube 20 a small are, according to indicator diagram 0 high temperatures of compression with gas and 011. v Finally the compression temperatures may be altered by precompression of the suction air. In Fig. 6 It" shows the motor, and m the compressor, which latter discharges the air through the suction pipe (1 into the combustion engine. The compressor is coupled to the engine shaft by means of an electroe magnetic friction coupling 6', if gas-oil working is desired. The governor, by means of contact f, when in its lowest positions, closes the circuit formed by the clutch energizing coil 6 and battery g.

In Fig. 7 the indicator diagrams of an ennor having provision for rendering said last,

named means inoperative when the engine speed increases to above a predetermined value.

2. An expansiblechamber type internal combustion engine installation having, in combination, means for delivering air to the combustion space of said engine, means for delivering gaseous fuel to said space, means for delivering liquid fuel directly to said space at the end portion of the compression stroke of said engine, a heater for said air, a governor responsive to engine load conditions, and meanscon'trolled by said governor for rendering inoperative said means for deelectric heating il i id d, I i livering liquid fuel and said heater when the cuit of the coil are the battery 3 the switch a and a contact a, the latter opened and closed by the governor.

In the lowest position the governor sleeves the contact is closed, and the heating coil warms the suction air in such a way, that the temperature .of compression is high enough to ignite the injected gas oil. If an oil of a lower flash point, say benzine is used, no prewarming of the air is necessary and contact 2 is switched out.

According to Fig. 5 an alteration of the com ression temperature may be effected by closing the inlet valve durin the last period of the suction stroke according to indicator diagram b, which diagram indicates the use of gas and benzine.

If the inlet valve is kept open during the whole period of stroke of the engine, there above a predeternor for rendering inoperative said means for delivering liquid fuel and said compressor when the engine speed increases to above a predetermined value.

4.. An expansible chamber type internal combustion engine installation having, in combination, means for delivering air to the KURT SCHMIDT. v 

